Solutions to Nikoli Hurdles 2 – Part 1/5

Puzzle 1: Masyu
Last year I conducted a poll asking for favourite Nikoli types. Masyu and Slitherlink were the two winners and became the Reader’s Choice for this edition of Nikoli Hurdles.

I quickly whipped up a 10×10 easy Masyu for Puzzle 1. The puzzle looked so boring that I decided to inject a bit more life into it. I aimed for a complete set of pentomino pieces in the givens but the grid was too big for uniqueness. I had to add more pieces and a few circles to get a valid puzzle.

A straight-forward solve to start the first 100m of the track

Puzzle 2: Yajilin
I picked one puzzle from the last Nikoli Hurdles to feature here and it was a Yajilin. An error posed a problem for early solvers when I had a 3 mistyped as a 2. Funnily, Prasanna who ran into the error; correctly assumed I had a typo and just tweaked the puzzle himself!

He continued the track without me even fixing it in time. About the solving, I thought it was a nice Yajilin with clue symmetry. Grandmaster Puzzles recommend using unclued grey boxes in Yajilins in which I can’t say I agree to. Those remind me of “cheater black squares” in American crossword puzzles. They’re there to make the author’s life easier while preserving the puzzle, which I don’t think is a pretty thing to do.

Nikoli Hurdles 5 [Live Updates]

[01 Dec] Nikoli Hurdles 5 has started!
Any updates or errata will be mentioned here.

– Password for Puzzle 4 had a minor typo. It is now fixed. Sorry!

[02 Dec] Puzzle 8 has been updated. The original one had multiple solutions. Please reload the page for the new version.

Welcome!

What do crosswords in your newspaper, that numbered 9x9 grid that’s suddenly everywhere, the spot the differences on a cereal box, a chess position from some tournament match, the squiggles you see in common IQ tests and a high school mathematics exam have in common?

Answer: They can all be classified as a “puzzle”.
As a lifelong puzzler, I always find the word “puzzle” to be a bit broad. Everyone has their own definition of a puzzle. I imagine a certain place where all puzzle types gather and made known to everyone. That place would be Somewhere Over the Rainbow.